Jan 18, 2017

Tennis and Transistors – A Story of Dr. H. C. Lin

Dr. Hung Chang Lin is referenced in many analog circuit patents and papers for several ideas: single-diode compensation for temperature stabilization in bipolar transistors, the use of a diode-connected transistor instead of an actual diode to improve matching, and the invention of lateral transistors. The audio community also references him for the so-called “quasi-complementary” output design, and later for “active noise cancellation.” He was a creative, energetic scientist at a key time in the early days of transistors and integrated circuits. He spent 20 years as a scientist, and 21 as a professor at the University of Maryland.

I was curious about his footsteps – where did he go to school, where did he work and what other analog greats had he crossed paths with? It wasn’t MIT, Stanford or Fairchild. Instead, biographers cite his BSEE from Chiao Tung University (Shanghai) in 1941, MSEE from the University of Michigan in 1948 and a PhD from the Polytechnic Institute of Brooklyn in 1956 (now part of NYU).

Hung Chang Lin was born in Shanghai in 1919, the son of Dr. Dao-Yang – the former president of Chung Chi College in Hong Kong. This was during the warlord period following the fall of the Qing Dynasty. The Kuomintang (KMT) enlisted help from the Soviet Union to defeat the warlords and unite the country, starting in northern China. The Soviet Union created the Communist Party of China (CPC) sowing the seeds of Civil War that would reach Shanghai by 1927 and drag on for ten years. The period from 1937 to 1945 was the Second Sino-Japanese War, the latter part of which coincided with World War II making China an ally of the United States against Japan. Somehow among all this, Lin attended Chiao Tung University on a tennis scholarship and studied electrical engineering. In those days, “electrical engineering” meant communications and utility power distribution. Chiao Tung University was modeled in many ways after American Universities and brought in American professors. It was encouraged for graduating students to travel to America for post-graduate education and work experience – sponsored at times by the government – and return to China later. It is quite likely that Lin was acquainted with An Wang, the founder of Wang Computers. Wang graduated a year prior to Lin, stayed another year to teach and then worked at China Central Radio Works before coming to America.

By 1937, Japan occupied Shanghai. Many of the students and faculty relocated to the French Concession, an area adjacent to Shanghai owned by the French until 1943. As the war continued, the university offered scholarships to maintain enrollment. In 1940, a state-run branch of the school was set up in Chongqing, the provisional capital of Chiang Kai-shek’s Nationalist government. Lin graduated before the occupying forces took over the Shanghai school in 1942. From there he worked as an engineer for the Central Radio Works in Kweilin and then the Central Broadcasting Administration in Kunmin, far to the southeast of Shanghai. There was a strong feeling of patriotism with many students joining the army and others serving technical roles. It is estimated that between 1 and 3.5 million Chinese died during the war. Wang lost his parents and a sister. In Wang’s autobiography, he said, “Confidence is sometimes rooted in the unpleasant, harsh aspects of life, and not in warmth and safety. It is an intangible quality but it has its own momentum. The longer you are able to survive and succeed, the better you are able to further survive and succeed.”

Lin moved to the United States in 1947, receiving his MSEE from the University of Michigan in 1948. This was shortly after Bell Laboratories had announced the invention of the transistor. The Radio Corporation of America (RCA) offered Lin a position in their patent department. RCA was eager to catch up with Bell Labs and quickly replicated their point contact transistor. In the early days of the transistor, RCA was second only to Bell Labs (Western Electric) in the number of transistor related patents. After working in the RCA patent office for two years, Lin moved to the Industry Service Laboratories group (RCA ISL) which had been formed to teach people how to use that patents they were licensing. This involved writing reports or visiting licensees to support the patent information. This was in contrast to the frustration felt by Bell/Western Electric licensees who were flooded with theory but little practical help to manufacture and utilize transistors.

For the 1952 ISL Symposium held at the RCA Labs in Princeton, NJ, Lin wanted to present something other than the transistor radios his colleagues were developing. He created a roving microphone and an audio amplifier. He also created a wireless, musical keyboard. Of his temperature compensation patent, he said,

“If I did make any contributions to early transistor technology, then my study of the temperature effect was one. In the early days, when we tried to bias transistors in the same way as was done for a vacuum tube, it wouldn’t work. You see, the heater for the tube keeps the internal temperature pretty constant, but in the transistor, the temperature depends on the ambient temperature, which can vary widely.”

“I built a 20 watt amplifier and took it to my boss to demonstrate, and took it outside where it was cold – it wouldn’t work. Another time, it overheated in use, and wouldn’t work. On the original 20 watt, I played music through a loudspeaker. I only needed one amplifier for monaural, because stereo was just coming out then. That amplifier really was one of my favorite circuits, because I used the so-called “Quasi- Complementary” design. I got a patent on this design and it is widely used today. You see at that time, we only had PNP (power) transistors, and these were all germanium. George Sziklai had just patented the complementary symmetry circuit (using both NPN and PNP), but we couldn’t get any good NPN (power) transistors, so that is why I developed the quasi-complementary.”

(Photo credit: Lin family photo)

Lin completed his PhD in Electrical Engineering from Polytechnic Institute of Brooklyn in 1956 while his wife, Anchen, worked to support them. That same year, he joined his friend Dr. Chu at Columbia Broadcasting Systems (CBS). CBS was a broadcasting company that wanted manufacturing capability and therefore had just acquired Hytron, a maker of TV tubes. This quickly progressed to semiconductors and Lin was hired to manage their applications group. Their biggest merchant business was power transistors for audio amplifiers in car radios. CBS ultimately divested this group in the 1960s.

George Sziklai joined Westinghouse and convinced them to hire Lin to work on integrated circuits in 1959. Lin recalled that in those days, anyone working on integrated circuits was considered a “laughing stock” by most of the industry. Westinghouse was heavily involved in military contracts and Lin was not immediately told the nature of his projects. In 1962, Autonetics was instrumental in forcing Westinghouse to abandon their mesa technology and develop a planar process similar to Fairchild’s. As part of the Minuteman II missile project in 1963, Westinghouse developed a differential amplifier. Texas Instruments, the other contractor, used a 4-layer PNPN process but this consistently failed radiation testing. This is when Lin came up with that lateral PNP which could be produced alongside an NPN transistor without any changes in processing or additional masking steps. Harry Knowles, Lin’s boss and a recent arrival from Motorola, bet Lin $5 that it wouldn’t work. Lin won. This is still widely used in analog integrated circuits, today.

Roughly parallel to all this, alumni of Chiao Tung University in New York helped resurrect the school in Hsinchu, Taiwan, officially established in 1958 as the National Chiao Tung University (NCTU). Initially, the only courses were in the Institute of Electronics. Lin and many others would support as visiting professors, conducting research and heading development projects. The establishment of the Semiconductor Lab in 1964 is considered the foundation of Taiwan’s semiconductor foundry industry. From the outset, the decision was made to focus on CMOS and to cooperate with RCA as its development partner. Dr. Lin was instrumental in fabricating NCTU’s first IC in 1966.

In 1969, Dr. “Jimmy” Lin joined the University of Maryland as a full-time professor where he only missed one class in the next 21 years. After his retirement in 1990, he continued to mentor students as Professor Emeritus. He held more than 60 patents, wrote the 1967 textbook “Integrated Circuits” and co-authored three others. He was elected a fellow of the IEEE and inducted into the Innovation Hall of Fame at the University of Maryland’s Clark School of Engineering. He was generous with his time and always remembered his fatherland. The Jimmy H. C. Lin Graduate Scholarship for Entrepreneurship supports graduate student applying from his Alma Mater, the Chiao Tung University in Taiwan and the (renamed) Jiao Tong University campuses in Shanghai and Xian.

About Me

I have always been fascinated by the history of whatever I'm doing: my job, the music I listen to, where I live. I love the old photos, I love finding the missing pieces of the puzzle, I love the personal stories.